In the letter, Pacific Rubiales highlights that the C$6.50 value is at
the high end of the valuation range given by an independent valuator
and provides immediate all-cash value for shareholders. The proposed
transaction offers certainty of value at a time of volatility and is in
the best interest of all shareholders.

LETTER TO SHAREHOLDERS

Dear Fellow Pacific Rubiales Shareholder:

As you know, we have called a Special Meeting of Shareholders to be held on July 7, 2015 to approve the proposed arrangement that would see ALFA, S.A.B. de C.V.
and Harbour Energy Ltd. acquire all of the Common Shares of the Pacific
Rubiales not already owned by them, for an all-cash price of C$6.50 per
share.

I wanted to reach out to all of you through this letter since we are at
a historic turning point for our Company. Our Board of Directors and
our Independent Committee are supportive of this proposal - not only
for the significant 81% all-cash premium it provides to all
Shareholders, but also because it represents a very important
de-risking opportunity for the future of Pacific Rubiales as compared
with the only other alternative available to us today: continuing to
pursue a "status quo" strategy.

I have always been optimistic about the prospects of Pacific Rubiales,
even in these uncertain times, but we must also recognize that in the
current oil price environment, absent the Transaction with ALFA and
Harbour Energy, the Company will have to devote most of its efforts to
continue its cost cutting initiatives, to find ways to increase our
efficiencies and to reduce our debt leverage to more manageable levels.
This will compromise our growth prospects.

It goes without saying that you can count on Management to continue to
perform through these difficult times, but also, you should be aware
that the mitigation of the downside risks, even when all possible
optimizations are considered, are almost fully dependent on an oil
price environment that is difficult to predict in the short to
mid-term.

BENEFITS OF THE C$6.50 OFFER TO ALL SHAREHOLDERS

Allow me now to restate what we believe are the main benefits of the
Transaction that it has been put before you:

Immediate all-cash value for Shareholders;

C$6.50 value is at the high end of the valuation range provided by an
independent valuator engaged by the Independent Committee in the
interests of Minority Shareholders;

Three financial advisors concluded the consideration is fair to
Shareholders, other than ALFA, from a financial point of view;

Certainty of value at a time of volatility in the oil markets;

Fully funded and not conditional on financing;

Unanimously recommended by the Board of Directors and the Independent
Committee; and

Overwhelmingly supported by our Creditors and Bondholders

WHY THE CURRENT OFFER IS BEST FOR ALL SHAREHOLDERS

After a comprehensive review and analysis, the Board of Directors, after
consulting with its financial and legal advisors, has adopted the
recommendation of the Independent Committee and has unanimously
determined that the Transaction is in the best interests of the Company
and that the Transaction is fair, from a financial point of view, to
the Shareholders (other than ALFA and its affiliates). Accordingly, the
Board of Directors unanimously recommends that the Shareholders vote in
favour of the Transaction. As directors and officers of the Company, we
are also supporting this Transaction by committing to vote all of our
Common Shares in favour of this offer.

The Independent Committee also reviewed and approved the request by ALFA
and Harbour Energy that Management remain and contribute their
contractual entitlements into the Company as part of the Transaction.
Management, in order to enable the Transaction, has committed to remain
in the Company and to contribute to the new vehicle their existing
entitlements, thereby assuming the implicit and substantial business
risks we have explained above, but doing so in order to remove a
potential obstacle in the path of the Transaction.

In making your decision, I urge you to consider the real risk that your
Common Shares will experience a significant decline in value if this
offer is not successful. Pacific Rubiales will continue to exist, of
that I have no doubt, but at low oil prices we will have limited growth
options and in all probability we will enter into a phase of production
maintenance and debt reduction for the foreseeable future.

At this critical moment in the history of our Company, I want to
encourage each of you to read the Management Information Circular dated
June 5, 2015, ask any questions you may have and focus on the merits of
the Transaction.

The Board of Directors and the Independent Committee have given
Shareholders a significant opportunity in these very uncertain times of
receiving cash for their shares at very substantial premium to market,
and have recommended you vote in favour of the C$6.50 all-cash offer.

Yours truly,

"Ronald Pantin"

Ronald PantinChief Executive Officer and Director

YOUR VOTE IS IMPORTANT REGARDLESS OF THE NUMBER OF COMMON SHARES YOU OWN. Registered holders of Common Shares who are unable to attend the
Meeting in person are requested to complete the BLUE Proxy Form for use at the Meeting or any adjournment or postponement
thereof.

To be effective, the BLUE Proxy Form must be submitted using one of the following methods:

delivery by facsimile to 416-595-9593;

delivery by mail so as to reach or be deposited with the Secretary of
the Corporation, c/o TMX Equity Transfer Services, at its offices at
200 University Avenue, Suite 300, Toronto, Ontario, Canada, M5H 4H1; or

electronically (at www.voteproxyonline.com)

in each case by no later than 9:00 a.m. (Vancouver time) / 12:00 noon
(Toronto time) on July 3, 2015, or in the event the Meeting is
adjourned or postponed, not less than 48 hours (excluding Saturdays,
Sundays and holidays) prior to the time set for any reconvened or
postponed Meeting. Please see the BLUE Proxy Form for more details. Non-registered Shareholders are advised to
refer to the Circular and to the Voting Instruction Form provided to
them for instructions relevant to them.

The special meeting is scheduled to be held on Tuesday, July 7, 2015 at
9:00 a.m. (PDT) / 12:00 noon (EDT) in the Saturna Room of the Fairmont
Hotel Vancouver, 900 West Georgia Street, Vancouver, British Columbia
(the "Meeting").

The board of directors of the Company has unanimously approved the Arrangement and recommends Shareholders vote their BLUE proxy FOR the arrangement by 9:00 a.m. (Vancouver time)/12:00 noon
(Toronto time) on Friday, July 3, 2015. Shareholders with questions
about voting their shares should call Kingsdale Shareholder Services at
1-877-659-1821 or 1-416-867-2272 outside of North America or email [email protected]

About Pacific Rubiales

Pacific Rubiales is a Canadian public company and a leading explorer and
producer of natural gas and crude oil, with operations focused in Latin
America. The Company has a diversified portfolio of assets with
interests in approximately 90 exploration and production blocks in
seven countries including Colombia, Peru, Guatemala, Brazil, Guyana,
Papua New Guinea and Belize. The Company's strategy is focused on
sustainable growth in production & reserves and cash generation.
Pacific Rubiales is committed to conducting business safely, in a
socially and environmentally responsible manner.

The Company's common shares trade on the Toronto Stock Exchange and La
Bolsa de Valores de Colombia under the ticker symbols PRE, and PREC,
respectively.

Advisories

Cautionary Note Concerning Forward-Looking Statements

This news release contains forward-looking statements. All statements,
other than statements of historical fact, that address activities,
events or developments that the Company believes, expects or
anticipates will or may occur in the future (including, without
limitation, statements regarding estimates and/or assumptions in
respect of production, revenue, cash flow and costs, reserve and
resource estimates, potential resources and reserves and the Company's
exploration and development plans and objectives) are forward-looking
statements. These forward-looking statements reflect the current
expectations or beliefs of the Company based on information currently
available to the Company. Forward-looking statements are subject to a
number of risks and uncertainties that may cause the actual results of
the Company to differ materially from those discussed in the
forward-looking statements, and even if such actual results are
realized or substantially realized, there can be no assurance that they
will have the expected consequences to, or effects on, the Company.
Factors that could cause actual results or events to differ materially
from current expectations include, among other things: uncertainty of
estimates of capital and operating costs, production estimates and
estimated economic return; the possibility that actual circumstances
will differ from the estimates and assumptions; failure to establish
estimated resources or reserves; fluctuations in petroleum prices and
currency exchange rates; inflation; changes in equity markets;
political developments in Colombia, Guatemala, Peru, Brazil, Papua New
Guinea, Guyana and Mexico; changes to regulations affecting the
Company's activities; uncertainties relating to the availability and
costs of financing needed in the future; the uncertainties involved in
interpreting drilling results and other geological data; and the other
risks disclosed under the heading "Risk Factors" and elsewhere in the
Company's annual information form dated March 18, 2015 filed on SEDAR
at www.sedar.com. Any forward-looking statement speaks only as of the date on which it
is made and, except as may be required by applicable securities laws,
the Company disclaims any intent or obligation to update any forward
looking statement, whether as a result of new information, future
events or results or otherwise. Although the Company believes that the
assumptions inherent in the forward-looking statements are reasonable,
forward-looking statements are not guarantees of future performance and
accordingly undue reliance should not be put on such statements due to
the inherent uncertainty therein. Forward-looking statements in this
news release are made pursuant to the "safe harbor" provisions of the
U.S. Private Securities Litigation Reform Act of 1995 and applicable
Canadian securities laws. When used herein, words such as "plan",
"target", "will", "expect", "anticipate", "estimate", "may", "should",
"intend", "believe", and similar expressions, are intended to identify
forward-looking statements. Forward-looking statements are based on
estimates and assumptions made by the parties in light of its
experience and its perception of historical trends, current conditions
and expected future developments, as well as other factors that the
parties believe are appropriate in the circumstances. Many factors
could cause such estimates and assumptions to vary or differ materially
from those expressed or implied by the forward-looking statements.
Readers should not place undue reliance on any of these forward-looking
statements.

This news release is being made for information purposes only and is not
intended to be, and must not be taken as, the basis for an investment
decision or any investment activity. This news release does not
constitute or form part of any offer or invitation to sell or issue, or
any solicitation of any offer to purchase or subscribe for, any
securities of Pacific Rubiales. The Company has issued a Management
Information Circular dated June 5, 2015 in connection with a special
meeting of shareholders of the Company to be held on July 7, 2015. Such
Circular and the related meeting materials contain important
information regarding the Transaction and such meeting. Such Circular
contains, among other things, a complete description of the
Transaction, reasons for and benefits of the Transaction, the
requirements for the Transaction to become effective, the interests of
directors and officers in the Transaction and information related to
voting at such meeting. Shareholders are encouraged to carefully review
the Circular and related meeting materials in their entirety. These
materials are available under the Company's profile on www.sedar.com. In addition, a copy of such materials can be obtained upon request by
contacting the Company Secretary at 416 362-7735.

Translation

This news release was prepared in the English language and subsequently
translated into Spanish. In the case of any differences between the
English version and its translated counterparts, the English document
should be treated as the governing version.